JP5333853B2 - Traction vehicle control device - Google Patents

Description

  The present invention relates to a control apparatus for a towing vehicle in which a trailer is slidably connected to a tractor via a hitch point.

  As a control device for a towing vehicle, Patent Document 1 monitors rolls during traveling of a connected vehicle in which a trailer is connected to an automobile, and when a roll motion is detected from this monitoring, the reverse of the roll is detected. A configuration is shown in which roll is suppressed by automatically generating a phase yaw moment. In particular, this Patent Document 1 shows a control mode for stabilizing a connected vehicle by an automatic brake that activates a brake only for a short time when there is at least one of a lateral acceleration and a yaw speed that are not based on steering of an automobile. Has been.

  As a control device for a tow vehicle, Patent Document 2 shows a tow vehicle in which a trailer is connected to a tractor. The difference in pressure between left and right airbags, brake cylinder pressure, steering angle, yawing rate, lateral acceleration, and wheel speed of a tractor are shown. Based on the evaluation. Based on this evaluation, a control configuration is described that reduces the occurrence of trailer jackknife, lateral swingout or combination spinning out, and trailer rollover.

  As a control device for a towing vehicle, Patent Document 3 discloses that a trailer is connected to a tractor to form a connected vehicle. The point to suppress is described. That is, in this patent document 3, the means for detecting the hitch angle, the brake for braking the trailer wheel, and the control means for operating the trailer brake when the hitch angle reaches a reference value or more are provided.

Special table 2003-503276 Japanese Patent Laid-Open No. 10-1037 Japanese Patent Laid-Open No. 10-236289

  If a sway phenomenon (snaking) occurs when the towing vehicle travels, the tractor and trailer swing around the hitch point, and the hitch point alternately protrudes in the left-right direction during this swing. . When the swing due to the sway phenomenon does not converge, the swing increases and the hitch point is greatly extended in the lateral direction, resulting in a disadvantage such as a jack knife phenomenon.

  In order not to cause such inconvenience, the tractor swings by applying an anti-phase moment based on either the lateral acceleration or the yaw speed in the tractor (automobile in the literature) as described in Patent Document 1. It is also possible to suppress this. However, in this control, although it is possible to suppress the swinging of the tractor by direct control with respect to the tractor, it is conceivable that the swinging of the trailer is insufficiently suppressed and the trailer continues to swing slightly.

  On the other hand, in Patent Document 2, the hitch angle and hitch angle rate are estimated (evaluated in the document) based on a plurality of information and reflected in the control, so that the swinging of the tractor and trailer is simultaneously suppressed. You can think it is possible. However, in the control of this Patent Document 2, it is necessary to detect the pressure difference between the left and right airbags (which seems to be an air suspension). Therefore, the attachment of a sensor for detecting pressure, the arrangement of a signal system from the sensor, etc. There is room for improvement.

  In Patent Document 3, since the control for suppressing the sway motion is performed based on the hitch angle, the swing of the tractor and the trailer can be simultaneously suppressed. However, the configuration of Patent Document 3 requires a sensor for detecting the hitch angle, and the arrangement of the signal system from the sensor is likely to be complicated, and there is room for improvement.

  An object of the present invention is to rationally configure a control device capable of stabilizing the behavior of a tow vehicle while suppressing an increase in the number of sensors.

A feature of the present invention is a control device for a towing vehicle in which a trailer is swingably connected to a tractor via a hitch point,
Lateral acceleration detecting means for detecting the lateral acceleration of the tractor, yaw rate detecting means for detecting the yaw rate of the tractor, steering angle detecting means for detecting the steering angle of the steered wheels of the tractor, and the traveling speed of the tractor are detected. A lateral speed detected by the lateral acceleration detection means, a yaw rate detected by the yaw rate detection means, a steering angle detected by the steering angle detection means, and the travel speed Hitch point lateral force estimating means for estimating the hitch point lateral force acting on the hitch point based on the traveling speed detected by the detecting means is provided, and the hitch point lateral force estimated by the hitch point lateral force estimating means is provided. The point is to determine the stability of the tow vehicle from the value.

According to this configuration, the hitch point lateral force estimating means estimates the hitch point lateral force acting on the hitch point based on the lateral acceleration, the yaw rate, the steering angle, and the traveling speed. Since the estimated hitch point lateral force reflects the swing amount of the tractor and the swing amount of the trailer, the stability of the towing vehicle can be determined based on the hitch point lateral force. In particular, the present invention does not require a sensor for detecting the angle of the hitch point. Therefore, a control device that can stabilize the behavior of the tow vehicle while suppressing an increase in the number of sensors has been configured.
In particular, in recent vehicles, the behavior of the vehicle body at the time of steering is detected by a sensor, and the ESC that realizes appropriate cornering by automatically controlling each brake and adjusting the engine output based on the detection result, etc. There are those equipped with a control device. As a sensor for detecting the behavior of the tractor, a yaw rate sensor, a lateral acceleration sensor, a steering angle sensor, a traveling speed sensor, and the like are provided. For this reason, the control of the present invention can be realized using an existing sensor of a control device such as an ESC.

  In the present invention, the tractor may include stabilization control means for stabilizing the attitude of the tow vehicle in accordance with the value of the hitch point lateral force.

  According to this configuration, the stabilization control means performs the stabilization control corresponding to the value of the hitch point lateral force, thereby realizing the rapid convergence of the sway phenomenon by the control suitable for suppression.

  In the present invention, the stabilization control means may be a moment generating means for generating a yaw moment in the direction opposite to the hitch point lateral force with respect to the tractor.

  Various external forces can be applied to the hitch point. However, when a yaw moment is generated in the tractor, the yaw moment can be efficiently applied to the hitch point lateral force from the opposite direction. For this reason, the moment generating means with this configuration efficiently applies a yaw moment in the reverse direction to the lateral force at the hitch point, thereby realizing stabilization of the towing vehicle.

  In the present invention, the stabilization control unit may be a braking force generation unit that generates a braking force on at least one of the wheels of the tractor.

  According to this configuration, the towing vehicle can be stabilized by the braking force generating means controlling the existing brake without using actuators for stabilizing the towing vehicle.

It is a top view which shows the structure of a tow vehicle. It is a schematic diagram which shows the lateral force which acts on the hitch point of a tow vehicle. It is a block diagram which shows the control structure of a tow vehicle. It is a figure which shows the balance relationship of the force which acts on a tow vehicle. It is the figure which showed the vehicle motion of the tractor with the two-wheel model. It is a block circuit diagram which shows the stabilization control part which implement | achieves the calculation of the calculation form 1. It is a flowchart which shows the calculation form of the calculation form 1. It is a block circuit diagram which shows the stabilization control part which implement | achieves the calculation of the calculation form 2. It is a figure which shows the balance relationship of the moment which acts on a tow vehicle. It is a flowchart which shows the calculation form of the calculation form 2.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[Basic configuration]
As shown in FIG. 1, a tow vehicle is configured by connecting a bracket 3 at the front end of a towed vehicle body B of a trailer 4 to a hitch 2 at the rear end of a self-propelled vehicle body A of a tractor 1 made of an automobile.

  The tractor 1 includes left and right front wheels 5 that function as steering wheels, and left and right rear wheels 6, and a gear that transmits a driving force by shifting from the engine 7 to at least one of the front wheels 5 and the rear wheels 6. A mechanism (not shown) is provided. The trailer 4 is provided with left and right trailer wheels 8 on the towed vehicle body B, and the bracket 3 is provided on the front end of the towed vehicle body B. The bracket 3 is swingably connected to a hitch point J constituted by a joint provided in the hitch 2. The trailer wheels 8 of the towed vehicle body B are not limited to two wheels, and may be four or more wheels.

  With such a configuration, the trailer 4 is towed as the tractor 1 travels, and the self-running vehicle body A of the tractor 1 and the towed vehicle body B of the trailer 4 bend around the longitudinal axis of the hitch point J during steering. It becomes a relative posture and a course change and a turn are realized.

  When the towing vehicle travels, a sway phenomenon (snaking) may occur in which the trailer 4 reciprocates in the left-right direction due to the road surface condition or the effect of crosswind. When this sway phenomenon occurs, the moment M1 acts on the towed vehicle body B of the trailer 4 as shown in FIG. 2 (a) due to the influence of the crosswind and road surface, and the hitch point J is set by the action of this moment M1. A hitch point lateral force Fh that projects laterally acts. When the hitch point lateral force Fh acts on the hitch point J as described above, the self-propelled vehicle body A of the tractor 1 is centered on the hitch point J by the hitch point lateral force Fh as shown in FIG. As a result of the moment M2 (yaw moment) acting on the tractor, the tractor 1 and the trailer 4 swing in a bent manner, and the hitch point J alternately protrudes in the left-right direction along with the swing.

  This is the sway phenomenon (snaking), and when the swing due to this sway phenomenon does not converge, the hitch point J protrudes greatly in the lateral direction by expanding the swing, resulting in inconvenience such as jackknife phenomenon. Invite.

  In the tow vehicle of the present invention, in a situation where the initial amplitude of the occurrence of the sway phenomenon is small, the control to suppress the sway phenomenon can be performed to prevent inconvenience such as the jackknife phenomenon. The configuration to be realized is described below.

As shown in FIGS. 1 and 3, the left and right front wheels 5 and the left and right rear wheels 6 of the self-propelled vehicle body A are each provided with a brake device BK that applies a braking force. A rotation speed sensor 11 for measuring the rotation speed with the wheel 6 is provided. The plurality of rotation speed sensors 11 also function as travel speed sensors. In addition, a brake device BK for applying a braking force to the trailer wheel 8 of the towed vehicle body B is provided. The brake device BK that applies a braking force to the trailer wheel 8 is assumed to be an actuator that operates with electric power to apply the braking force. However, a device that uses hydraulic pressure or air may be used.
Further, the brake device BK on the trailer side is not essential, and the brake device BK may be provided only on the self-propelled vehicle body A without providing the brake device on the trailer side, as is often seen in particularly light weight trailers.

  The self-propelled vehicle body A includes a steering angle sensor 13 (an example of a steering angle detection unit) that detects a steering amount by the steering wheel 12, an accelerator pedal sensor 14S that detects a depression operation amount of the accelerator pedal 14, and a brake pedal 15. A brake pedal sensor 15S for detecting a stepping operation is provided. The self-running vehicle body A includes a yaw rate sensor 16 (an example of a yaw rate detection unit) that detects a yaw rate, and a lateral acceleration sensor 17 (an example of a lateral acceleration detection unit) that detects a lateral acceleration acting on the self-running vehicle body A. And a control device 20.

[Control configuration]
As shown in FIG. 3, in the self-propelled vehicle body A, the steering angle sensor 13, the accelerator pedal sensor 14S, the brake pedal sensor 15S, the yaw rate sensor 16, the lateral acceleration sensor 17, and the control device 20 are connected by a communication line L formed of a CAN bus. Has been. A brake control ECU 25, an engine control ECU 27, an automatic transmission ECU 29, and a communication unit 31 are connected to the communication line L. The brake control ECU 25 controls the electromagnetic valve of the brake pressure control unit 26. The engine control ECU 27 controls the throttle unit 28 of the engine 7. The automatic transmission ECU 29 controls the transmission unit 30 of a transmission (not shown).

  The towed vehicle body B includes a communication unit 32 that is connected to the communication unit 31 of the self-propelled vehicle body A via a communication cable C, and the brake control ECU 33 is connected to the communication unit 32 by a communication line L formed of a CAN bus. ing. A brake operation unit 34 and a brake lamp 35 are connected to the brake control ECU 33, and the brake operation unit 34 is connected to operate the left and right brake devices BK. In this towing vehicle, when a braking force is applied to each wheel by depressing the brake pedal 15, the brake lamp 35 is turned on.

  The control device 20 realizes the stable control of the present invention. The control device 20 can use a conventional control device that performs anti-lock brake control, traction control, and ESC control.

  More specifically, the control device 20 includes an antilock brake control unit 21 that implements antilock brake control, a traction control unit 22, and a stabilization control unit 23 (an example of a stabilization control unit).

  Anti-lock brake control is also referred to as ABS, and feeds back the rotation state (lock state) of each wheel when the brake pedal 15 is depressed, and the brake pressure control unit 26 adjusts the brake pressure so as to prevent the wheel from being locked. To eliminate skid caused by wheel locks.

Traction control is also referred to as TCS, which feeds back the rotation state (wheel spin state) of each wheel when the accelerator pedal 14 is depressed, and prevents the wheel spin from being caused by the brake pressure control unit 26 and the engine control ECU 27. The driving force is adjusted to eliminate skid caused by vehicle wheel spin.
In the conventional ESC control, when the steering wheel 12 is operated, the self-propelled vehicle body A is based on the traveling speed detected by the rotation speed sensor 11 (functioning as a traveling speed sensor) and the yaw rate detected by the yaw rate sensor 16. Understeer and oversteer by controlling each brake device BK, adjusting the output of the engine 7, and automatically shifting the transmission so that the cornering is appropriate based on this behavior. Suppressed.

Compared to the conventional ESC control, the vehicle body stabilization control determines the stability of the tow vehicle by estimating the lateral force acting on the hitch point J. By controlling the brake device BK of the traveling vehicle body A, a canceling yaw moment is applied to suppress the sway phenomenon, and the control mode will be described below. In the vehicle body stabilization control, not only the action of the braking force by the brake device BK, but also a control in which a canceling yaw moment is applied by increasing the speed of one of the left and right wheels. In addition, when the canceling yaw moment is applied, the engine control ECU 26 or the automatic transmission ECU 29 may perform control to reduce the vehicle speed.
Further, in this embodiment, the control device 20 and the brake control ECU 25 are provided separately and connected by the communication line L. However, the control device 20 and the brake control ECU 25 may be configured integrally without the communication line L. good.

  The antilock brake control unit 21, the traction control unit 22, and the stabilization control unit 23 are configured by software, but may be configured by software and hardware such as logic, You may comprise only hardware.

[Calculation form 1]
FIG. 4 shows a front wheel lateral force Ff acting laterally on the front wheel 5 of the self-propelled vehicle A, a rear wheel lateral force Fr acting laterally on the rear wheel 6, and a hitch point J acting laterally. The relationship between the hitch point lateral force Fh to be balanced is shown. Further, this balanced relationship can be shown as a relational expression in FIG. In this [Calculation Mode 1], the stabilization control unit 23 determines the force balance relationship, the traveling speed V, the steering angle δf, the yaw rate Yr, the lateral acceleration GY acting on the center of gravity X, and the weight M. Based on this, the hitch point lateral force Fh is estimated (see FIG. 5). In FIG. 4, the direction in which each force acts is indicated by an arrow.

As shown in FIG.
The balance relationship is expressed by Ff + Fr + Fh = M × GY [Formula 1].
In FIG. 4, a sign (+) is added to the force acting in the left direction of the self-propelled vehicle body A, and a sign (-) is added to the force acting in the right direction of the self-propelled vehicle body A. Yes. A calculation for estimating the hitch point lateral force Fh is performed based on this relational expression.

  The stabilization controller 23 includes a wheel slip angle calculator 23A, a wheel lateral force calculator 23B, a hitch point lateral force estimator 23C (an example of a hitch point lateral force estimator), an offset yaw moment calculator 23D, A yaw moment output unit 23E (an example of a moment generating means) and an information table 23F are provided. The calculation process based on these will be described with reference to the block circuit of FIG. 6 and the flowchart of FIG.

  When the steering wheel 12 is in a non-steering state (straight forward position) during traveling of the towing vehicle, signals from the sensors are acquired, and the vehicle body slip angle β is calculated by calculation. Based on this, the front wheel slip angle βf The rear wheel slip angle βr is calculated (steps # 101 to # 104).

  The signals acquired from each sensor include a traveling speed V based on a signal from the rotation speed sensor 11, a steering angle δ detected by the steering angle sensor 13, a yaw rate Yr detected by the yaw rate sensor 16, and a lateral acceleration. The lateral acceleration GY measured by the sensor 17 is acquired.

  FIG. 5 shows the vehicle motion in the two-wheel model when the self-propelled vehicle body A is steered. In the figure, the distance from the center of gravity X to the front wheel 5 (distance to the front axle) is Lf, and the distance from the center of gravity X to the rear wheel 6 (distance to the rear axle) is Lr. In the same figure, the traveling speed V, the yaw rate Yr, the vehicle body slip angle β, the front wheel slip angle βf, the rear wheel slip angle βr, the lateral acceleration GY, when the front wheel 5 is operated by the steering angle δf, The front wheel lateral force Ff and the rear wheel lateral force Fr are shown.

  From this motion characteristic, it is known that the following relational expressions [Formula 2] to [Formula 6] hold.

β = ∫ (GY / V−Yr) dt [Formula 2]
βf = β + (Lf × Yr / V) −δf [Formula 3]
βr = β− (Lf × Yr / V) [Formula 4]
Fh = −Cpf × βf [Formula 5]
Fr = −Cpr × βr [Formula 6]

  In the wheel slip angle calculation unit 23A, among these relational expressions, [Expression 2] to [Expression 4], the traveling speed V detected by the rotation speed sensor 11 functioning as a traveling speed sensor, and the steering angle sensor 13 are detected. The steering angle δ, the yaw rate Yr detected by the yaw rate sensor 16, and the lateral acceleration GY detected by the lateral acceleration sensor 17 are acquired. And this wheel slip angle calculating part 23A calculates vehicle body slip angle (beta), and calculates front wheel slip angle (beta) f and rear wheel slip angle (beta) r based on this.

  Here, the front cornering power Cpf and the rear cornering power Cpr are values determined by the tire characteristics and the load on the tire.

  In this embodiment, Cpf and Cpr obtained in advance by a running test or the like are stored in the information table 23F, and the stabilization control unit 23 shown in FIG. A processing mode to be read is set.

  Next, the wheel lateral force calculation unit 23B determines that the front wheel lateral force Ff and the rear wheel are based on [Formula 5] and [Formula 6] of these relational expressions, and the front wheel slip angle βf and the rear wheel slip angle βr. The wheel lateral force Fr is calculated.

  Then, the hitch point lateral force estimating unit 23C estimates the hitch point lateral force Fh by the calculation based on [Equation 1] described above based on the front wheel lateral force Ff and the rear wheel lateral force Fr (step # 105). .

  In step # 105, after calculating the front wheel lateral force Ff and the rear wheel lateral force Fr, a process of estimating the hitch point lateral force Fh based on the lateral acceleration GY and the weight M is executed. A process of estimating the hitch point lateral force Fh based on the slip angle βf, the rear wheel slip angle βr, the front cornering power Cpf, and the rear cornering power Cpr may be executed.

  When the sway phenomenon has occurred, the hitch point lateral force Fh described above repeatedly increases and decreases between positive and negative signs. For this reason, when the canceling yaw moment calculating unit 23D next determines the stability by comparing the maximum value of the absolute value of the hitch point lateral force Fh with the threshold value, and exceeds the threshold value. When it is determined that it is not stable, a canceling yaw moment that is opposite to the hitch point lateral force Fh is calculated. The canceling yaw moment is calculated based on the distance Lh from the hitch point J to the center of gravity X of the tractor 1 and the value of the hitch point lateral force.

The yaw moment output unit 23E selects at least one of the front wheel 5 and the rear wheel 6 of the tractor 1 as a braking target, and the distance Lh from the hitch point J to the center of gravity X of the tractor 1 and the center of gravity from the front wheel 5 Based on the distance Lf to X, the distance Lr from the rear wheel 6 to the center of gravity X, and the calculated value of the canceling yaw moment, the braking force to be applied to the brake device BK of the selected wheel is set.
In this case, when one of the left and right front wheels 5 and rear wheels 6 of the tractor 1 is selected as a braking target, the yaw moment can be generated efficiently.
Furthermore, you may correct | amend a braking timing and braking force according to a rocking | fluctuation period.
Then, the yaw moment output unit 23E controls the brake control ECU 25 to apply the calculated braking force to the brake device BK to be braked by the tractor 1 to generate a canceling yaw moment, thereby causing the sway phenomenon. Suppression can be achieved (steps # 106 to # 108).
When it is determined that the canceling yaw moment calculating unit 23D is not stable, the trailer-side brake device BK may be applied in addition to the brake device BK of the tractor 1.

  In particular, the canceling yaw moment calculator 23D calculates a canceling yaw moment that causes a force greater than the hitch point lateral force Fh (a force approximately 1.2 times) to act on the hitch point J in the reverse direction. That is, when the canceling yaw moment is set so that a force equal to the hitch point lateral force Fh is applied, only the swing of the self-propelled vehicle body A converges and the swing of the towed vehicle body B may remain. In order to suppress such a phenomenon and quickly converge the sway phenomenon, the canceling yaw moment is set by multiplying the moment value for canceling the hitch point lateral force Fh by a coefficient of about 1.2. It is. The value of this coefficient can be any value. For example, when it takes time to converge the fluctuation due to the sway phenomenon, the coefficient is increased so that the coefficient is adjusted based on the time until convergence. The form may be set.

Further, the value of the canceling yaw moment calculated by the canceling yaw moment calculating unit 23D may be set to a value that cancels the hitch point lateral force Fh, and the force applied to the brake device BK may be increased.
In this case, the yaw moment output unit 23E selects the left and right wheels as a braking target at least one of the front wheels 5 or the rear wheels 6 of the self-propelled vehicle body A, and maintains the brake force difference between the left and right wheels. By increasing the sum of the forces, the vehicle deceleration can be increased while maintaining the offset yaw moment.
As a result, the self-propelled vehicle body A and the towed vehicle body B are converged by the canceling yaw moment, and at the same time, the stability of the towed vehicle body B can be improved by reducing the speed of the vehicle faster.
Even in such a control mode, in the same way as described above, when it takes time to converge the swing due to the sway phenomenon, the control mode is set so that the increase amount of the braking force is adjusted based on the time until the convergence. Also good.
However, if a strong braking force is applied only to the self-propelled vehicle A while the towed vehicle B is swinging, the towed vehicle B shows a jackknife tendency. Therefore, the amount of increase in braking force and the deceleration of the generated vehicle are It is desirable to set an upper limit value.

[Calculation form 2]
FIG. 9 shows the front wheel moment (Lf × Ff) acting laterally on the front wheel 5 with respect to the center of gravity X of the self-propelled vehicle A and the rear wheel 6 with respect to the center of gravity X of the self-propelled vehicle A. The acting rear wheel moment (Lr × Fr), the hitch point moment (Lh × Fh) acting laterally on the hitch point J with reference to the center of gravity X of the self-propelled vehicle A, and the center of gravity X of the self-propelled vehicle A 2 shows a relationship balanced with the vehicle body moment (Iz × dYr) acting on the. In the figure, the direction in which each force acts is indicated by an arrow.

  In the figure, the distance to the front wheel 5 (front axle) is defined as Lf based on the center of gravity X of the self-propelled vehicle A, and the distance to the rear wheel 6 (rear axle) based on the center of gravity X of the self-propelled vehicle A. The distance to the hitch point J is described as Lh with the center of gravity X of the self-propelled vehicle body A as a reference. Ff is the front wheel lateral force, Fr is the rear wheel lateral force, Fh is the hitch point lateral force, Iz is the yaw moment of inertia (a constant of the vehicle body), and dYr is the yaw acceleration.

  In this [Calculation Mode 2], the stabilization control unit 23 determines the moment balance relationship, the traveling speed V, the steering angle δf, the yaw rate Yr, the lateral acceleration GY acting on the center of gravity X, the weight M, The hitch point lateral force Fh is estimated based on necessary constants and the like.

As shown in the figure,
The balance of moment is expressed by Lf × Ff−Lr × Fr−Lh × Fh = Iz × dYr [Formula 11].
In FIG. 9, a + (plus) sign is attached to the moment acting on the left side of the self-propelled vehicle body A, and a − (minus) sign is attached to the moment acting on the right side of the self-running vehicle body A. . A calculation for estimating the hitch point lateral force Fh is performed based on this relational expression.

  In [Calculation Mode 2], as in [Calculation Mode 1], the stabilization control unit 23 includes a wheel slip angle calculation unit 23A, a wheel lateral force calculation unit 23B, and a hitch point lateral force estimation. 23C, an offset yaw moment calculator 23D, a yaw moment output unit 23E, and an information table 23F. The calculation process based on these will be described with reference to the block circuit of FIG. 8 and the flowchart of FIG.

  In the situation where the steering wheel 12 is in a non-steering state (straight forward position) when the towing vehicle is traveling, a signal from each sensor is obtained and a vehicle body slip angle β is calculated by calculation, and based on this, a front wheel slip angle βf And rear wheel slip angle βr are calculated (# 201 to # 204).

  Also in this relational expression, the wheel slip angle calculation unit 23A calculates the vehicle body slip angle β based on [Formula 2] to [Formula 4] described in [Calculation form 1], as in [Calculation form 1]. Based on this, the front wheel slip angle βf and the rear wheel slip angle βr are calculated. Also in [Calculation Mode 2], the front cornering power Cpf and the rear cornering power Cpr are values determined by the tire characteristics and the load on the tire, and Cpf and Cpr obtained in advance by a running test or the like are stored in the information table 23F. It is stored. In the stabilization control unit 23 shown in FIG. 8, a processing mode for reading the front cornering power Cpf and the rear cornering power Cpr from the information table 23F is set.

  Further, the wheel lateral force calculation unit 23B determines that the front wheel lateral force Ff and the rear wheel are based on [Formula 5] and [Formula 6] described in [Calculation Mode 1], and the front wheel slip angle βf and the rear wheel slip angle βr. The wheel lateral force Fr is calculated.

  Then, the hitch point lateral force estimating unit 23C estimates the hitch point lateral force Fh by the calculation based on the above-described [Equation 11] based on the front wheel lateral force Ff and the rear wheel lateral force Fr (step # 205). .

  In step # 205, after calculating the front wheel lateral force Ff and the rear wheel lateral force Fr, a process of estimating the hitch point lateral force Fh based on the lateral acceleration GY and the weight M is executed. A process of estimating the hitch point lateral force Fh based on the slip angle βf, the rear wheel slip angle βr, the front cornering power Cpf, and the rear cornering power Cpr may be executed.

  When the sway phenomenon has occurred, the hitch point lateral force Fh described above repeatedly increases and decreases between positive and negative signs. For this reason, when the canceling yaw moment calculating unit 23D next determines the stability by comparing the maximum value of the absolute value of the hitch point lateral force Fh with the threshold value, and exceeds the threshold value. When it is determined that it is not stable, a canceling yaw moment that is opposite to the hitch point lateral force Fh is calculated. The canceling yaw moment is calculated based on the distance Lh from the hitch point J to the center of gravity X of the tractor 1 and the value of the hitch point lateral force Fh.

The yaw moment output unit 23E selects at least one of the front wheel 5 and the rear wheel 6 of the tractor 1 as a braking target, and the distance Lh from the hitch point J to the center of gravity X of the tractor 1 and the center of gravity from the front wheel 5 Based on the distance Lf to X, the distance Lr from the rear wheel 6 to the center of gravity X, and the calculated value of the canceling yaw moment, the braking force to be applied to the brake device BK of the selected wheel is set.
In this case, when one of the left and right front wheels 5 and rear wheels 6 of the tractor 1 is selected as a braking target, the yaw moment can be generated efficiently.
Furthermore, you may correct | amend a braking timing and braking force according to a rocking | fluctuation period.
The yaw moment output unit 23E controls the brake control ECU 25 to apply the calculated braking force to the brake device BK to be braked by the tractor 1 to generate a canceling yaw moment, thereby suppressing the sway phenomenon. (Steps # 206 to # 208).
When it is determined that the canceling yaw moment calculating unit 23D is not stable, the trailer-side brake device BK may be applied in addition to the brake device BK of the tractor 1.

  In particular, in the canceling yaw moment calculating unit 23D, as in [Calculation Form 1], a canceling yaw that causes a force greater than the hitch point lateral force Fh (a force approximately 1.2 times) to act on the hitch point J in the opposite direction. The moment is calculated. That is, when the canceling yaw moment is set so that a force equal to the hitch point lateral force Fh is applied, only the swing of the self-propelled vehicle body A converges and the swing of the towed vehicle body B may remain. In order to suppress such a phenomenon and quickly converge the sway phenomenon, the canceling yaw moment is set by multiplying the moment value for canceling the hitch point lateral force Fh by a coefficient of about 1.2. It is. The value of this coefficient can be any value. For example, when it takes time to converge the fluctuation due to the sway phenomenon, the coefficient is increased so that the coefficient is adjusted based on the time until convergence. The form may be set.

In [Calculation Mode 2], similarly to [Calculation Mode 1], the value of the cancellation yaw moment calculated by the cancellation yaw moment calculation unit 23D is set to a value that cancels the hitch point lateral force Fh. The force applied to the brake device BK may be increased.
In this case, the yaw moment output unit 23E selects the left and right wheels as a braking target at least one of the front wheels 5 or the rear wheels 6 of the self-propelled vehicle body A, and maintains the brake force difference between the left and right wheels. By increasing the sum of the forces, the vehicle deceleration can be increased while maintaining the offset yaw moment.
As a result, the self-propelled vehicle body A and the towed vehicle body B are converged by the canceling yaw moment, and at the same time, the stability of the towed vehicle body B can be improved by reducing the speed of the vehicle faster.
Even in such a control mode, in the same way as described above, when it takes time to converge the swing due to the sway phenomenon, the control mode is set so that the increase amount of the braking force is adjusted based on the time until the convergence. Also good.
However, if a strong braking force is applied only to the self-propelled vehicle A while the towed vehicle B is swinging, the towed vehicle B shows a jackknife tendency. Therefore, the amount of increase in braking force and the deceleration of the generated vehicle are It is desirable to set an upper limit value.

[Operation / Effect Based on Calculation Form 1 and Calculation Form 2]
As described above, according to the present invention, the sensors used in the control device 20 made of ESC conventionally provided in the vehicle body are used as they are, so that the hitch point J is not provided with a special sensor for detecting the angle of the hitch. The hitch point lateral force Fh acting on the point J can be estimated. Then, the degree of the sway phenomenon is grasped from the magnitude of the hitch point lateral force Fh calculated in this way, and it becomes possible to determine whether or not the suppression is necessary, and an optimum canceling yaw moment is obtained by operating the brake device BK. By making it act, suppression of the sway phenomenon at the initial stage is realized.

  In particular, in the present invention, two types of hitch point lateral forces Fh based on different calculation processes are estimated by performing [Calculation Mode 1] and [Calculation Mode 2] in parallel. Processing to calculate the canceling yaw moment based on the average value of the hitch point lateral force Fh, or canceling based on the other value without using a numerical value that can be judged as abnormal among the two types of hitch point lateral force Fh The processing mode may be set so as to calculate the yaw moment. With such a configuration, reliability can be improved.

  The present invention can be used for general control for suppressing the sway phenomenon of a tow vehicle.

1 Tractor 4 Trailer 5 Steering wheel / wheel (front wheel)
6 wheels (rear wheels)
8 Trailer wheels 11 Travel speed sensor (rotation speed sensor)
13 Steering angle detection means (steering angle sensor)
16 Yaw rate detection means (yaw rate sensor)
17 Lateral acceleration detection means (lateral acceleration sensor)
23 Stabilization control means (stabilization control unit)
23C Hitch point lateral force estimating means (hitch point lateral force estimating unit)
23E Moment generation means (yaw moment output section)
J Hitch point Fh Hitch point lateral force

Claims (4)

A control device for a towing vehicle in which a trailer is connected to a tractor through a hitch point so as to be swingable.
Lateral acceleration detecting means for detecting the lateral acceleration of the tractor, yaw rate detecting means for detecting the yaw rate of the tractor, steering angle detecting means for detecting the steering angle of the steered wheels of the tractor, and the traveling speed of the tractor are detected. A traveling speed detecting means for performing
The lateral acceleration detected by the lateral acceleration detecting means, the yaw rate detected by the yaw rate detecting means, the steering angle detected by the steering angle detecting means, and the traveling speed detected by the traveling speed detecting means A hitch point lateral force estimating means for estimating a hitch point lateral force acting on the hitch point based on the hitch point lateral force estimating means, and determining the stability of the tow vehicle from the hitch point lateral force value estimated by the hitch point lateral force estimating means. Towing vehicle control device.   The tow vehicle control device according to claim 1, wherein the tractor includes a stabilization control unit that stabilizes a posture of the tow vehicle in accordance with a value of the hitch point lateral force.   The tow vehicle control device according to claim 2, wherein the stabilization control means is a moment generation means for generating a yaw moment in a direction opposite to the hitch point lateral force with respect to the tractor.   The tow vehicle control device according to claim 3, wherein the stabilization control means is a braking force generation means for generating a braking force on at least one of the wheels of the tractor.

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